Alert archive / California / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 30, NWS Phoenix, AZ

August 6, 2015Riverside County, San Bernardino County, California

NWS Phoenix, AZ issued this severe thunderstorm warning at Aug 6, 2015, 9:27 PM PDT for Riverside County, San Bernardino County, California. It was in force for 33 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 6, 2015, 9:27 PM PDT (04:27 UTC)
Expired
Aug 6, 2015, 10:00 PM PDT
In force
33 min
Issued by
NWS Phoenix, AZ
Area
Storm-based polygon

Counties Riverside County, CA, San Bernardino County, CA

The radar

The Santa Ana Mts radar (KSOX), 152 km from the middle of the area, began a volume at 04:28 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

San Diego, CA (KNKX), launched 00:00Z, 4.5 hours before the alert went out and 195 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, San Diego, CA at 00:00Z on 2015-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, San Diego, CA at 00:00Z on 2015-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2253 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Phoenix, AZ wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 6, 7:03 PM PDT, 2 hours 24 minutes earlier.

Area forecast discussion, Aug 6, 7:03 PM PDT, 2 hours 24 minutes before
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In the hours before

Special weather statement, Aug 6, 3:43 PM PDT, 5 hours 44 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
343 PM PDT THU AUG 6 2015

CAZ031>033-062315-
IMPERIAL COUNTY CA-RIVERSIDE COUNTY/EASTERN DESERTS CA-
LOWER COLORADO RIVER VALLEY CA CA-
343 PM PDT THU AUG 6 2015

...SIGNIFICANT WEATHER ADVISORY...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

SIGNIFICANT WEATHER ADVISORY FOR...
  SOUTHEASTERN RIVERSIDE AND NORTH CENTRAL IMPERIAL COUNTIES

UNTIL 415 PM PDT

AT 343 PM PDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM 15
MILES WEST OF PALO VERDE...OR 29 MILES SOUTHEAST OF DESERT CENTER...
MOVING NORTH AT 10 MPH.

WIND GUSTS UP TO 50 MPH WILL BE POSSIBLE WITH THIS STORM.

THIS STORM WILL REMAIN OVER MAINLY RURAL AREAS OF SOUTHEASTERN
RIVERSIDE AND NORTH CENTRAL IMPERIAL COUNTIES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

LOCALLY DENSE BLOWING DUST IS POSSIBLE.  IF YOU ENCOUNTER BLOWING
DUST WHILE DRIVING...PULL OVER AS FAR OFF THE ROADWAY AS POSSIBLE AND
PARK. TURN OFF YOUR HEADLIGHTS AND KEEP YOUR FOOT OFF THE BRAKE.

&&

LAT...LON 3339 11486 3338 11510 3359 11514 3359 11480
TIME...MOT...LOC 2243Z 181DEG 10KT 3347 11499

18
Special weather statement, Aug 6, 5:04 PM PDT, 4 hours 23 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
504 PM MST THU AUG 6 2015

AZZ026-070030-
SOUTHWEST DESERTS AZ-
504 PM MST THU AUG 6 2015

...SIGNIFICANT WEATHER ADVISORY...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

SIGNIFICANT WEATHER ADVISORY FOR...
  CENTRAL YUMA COUNTY

UNTIL 530 PM MST

AT 504 PM MST...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM OVER
TACNA...OR 25 MILES EAST OF FORTUNA FOOTHILLS...MOVING NORTH AT 10
MPH.

WIND GUSTS UP TO 50 MPH WILL BE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
TACNA AND ROLL.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

LOCALLY DENSE BLOWING DUST IS POSSIBLE.  IF YOU ENCOUNTER BLOWING
DUST WHILE DRIVING...PULL OVER AS FAR OFF THE ROADWAY AS POSSIBLE AND
PARK. TURN OFF YOUR HEADLIGHTS AND KEEP YOUR FOOT OFF THE BRAKE.

&&

LAT...LON 3265 11389 3263 11403 3279 11412 3283 11388
TIME...MOT...LOC 0004Z 170DEG 9KT 3269 11397

18
Local storm report, Aug 6, 5:34 PM PDT, 3 hours 53 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
534 PM MST THU AUG 06 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0440 PM     DUST STORM       2 WSW TACNA             32.68N 113.98W
08/06/2015                   YUMA               AZ   TRAINED SPOTTER

            VSBY LESS THAN 0.25 MI. AND ESTIMATED WIND GUSTS TO 40
            MPH

&&

EVENT NUMBER PSR1500095

PSR
Special weather statement, Aug 6, 7:14 PM PDT, 2 hours 13 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PHOENIX AZ
714 PM PDT THU AUG 6 2015

CAZ033-070230-
IMPERIAL COUNTY CA-
714 PM PDT THU AUG 6 2015

...SIGNIFICANT WEATHER ADVISORY...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A

SIGNIFICANT WEATHER ADVISORY FOR...
  NORTHWESTERN IMPERIAL COUNTY

UNTIL 730 PM PDT

AT 714 PM PDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR
SALTON CITY...MOVING NORTH AT 40 MPH.

WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
SALTON CITY...DESERT SHORES...SALTON SEA BEACH...WINONA AND COOLIDGE
SPRINGS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

LOCALLY DENSE BLOWING DUST IS POSSIBLE.  IF YOU ENCOUNTER BLOWING
DUST WHILE DRIVING...PULL OVER AS FAR OFF THE ROADWAY AS POSSIBLE AND
PARK. TURN OFF YOUR HEADLIGHTS AND KEEP YOUR FOOT OFF THE BRAKE.

&&

LAT...LON 3308 11609 3312 11608 3342 11608 3342 11579
      3299 11595 3306 11611
TIME...MOT...LOC 0214Z 187DEG 36KT 3327 11605

18
Special weather statement, Aug 6, 7:46 PM PDT, 1 hour 41 minutes before
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Special weather statement, Aug 6, 9:11 PM PDT, 16 minutes before
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The office that day

Everything else NWS Phoenix, AZ issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 6, 5:04 PM PDTSpecial Weather StatementPSRYuma26 min
Aug 6, 7:14 PM PDTSpecial Weather StatementPSR16 min
Aug 6, 9:41 PM PDTSpecial Weather StatementPSR34 min
Aug 7, 6:06 AM PDTSpecial Weather StatementPSR39 min
Aug 7, 6:52 AM PDTSpecial Weather StatementPSRPinal38 min
Aug 7, 7:29 AM PDTSpecial Weather StatementPSR46 min
Aug 7, 11:41 AM PDTSpecial Weather StatementPSRGila49 min
Aug 7, 11:44 AM PDTSpecial Weather StatementPSRGila46 min
Aug 7, 11:51 AM PDTSpecial Weather StatementPSRGila54 min
Aug 7, 11:56 AM PDTSevere Thunderstorm WarningPSRGila49 min
Aug 7, 12:21 PM PDTAreal Flood AdvisoryPSRGila3 hr
Aug 7, 12:29 PM PDTSpecial Weather StatementPSRGila61 min
Aug 7, 12:53 PM PDTSpecial Weather StatementPSRGila82 min
Aug 7, 1:25 PM PDTFlash Flood WarningPSRGila3 hr
Aug 7, 1:54 PM PDTBlowing Dust AdvisoryPSR2 hr
Aug 7, 2:16 PM PDTFlash Flood WarningPSRGila3 hr
Aug 7, 2:22 PM PDTSpecial Weather StatementPSRGila53 min
Aug 7, 2:28 PM PDTSevere Thunderstorm WarningPSRPinal17 min
Aug 7, 3:19 PM PDTSpecial Weather StatementPSRPinal41 min
Aug 7, 4:20 PM PDTSpecial Weather StatementPSR25 min
Aug 7, 4:47 PM PDTSpecial Weather StatementPSRMaricopa43 min
Aug 6, 7:26 PM PDTSevere Thunderstorm WarningPSRImperial, Riverside19 min
Aug 6, 7:46 PM PDTSpecial Weather StatementPSRRiverside29 min
Aug 6, 9:11 PM PDTSpecial Weather StatementPSRRiverside34 min
Aug 6, 10:54 PM PDTSpecial Weather StatementPSRRiverside36 min
Aug 7, 12:46 AM PDTAreal Flood AdvisoryPSRRiverside, San Bernardino3 hr

Nearby

Severe Thunderstorm Warnings in California, 2015Every severe thunderstorm warning in 2015

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.